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NORTH AMERICAN FAUNA 74 



during the winter, when accidentally caught between ice floes in a storm at the 

 edge of the pack. However, the walrus population in winter does not generally 

 inhabit the edge of the pack, where storm conditions prevail, but resides well 

 north of it where the floes are much larger, more stable, and where there is little 

 or no risk of being crushed. 



Murie (1936) reported the finding by O. W. Geist of several walrus bones with 

 healed fractures in archaeological materials from St. Lawrence Island. These 

 included one tibia, one scapula, and two examples of extensive exostosis in the 

 costo-sternal area. Not mentioned by Murie was the fact that his specimens were 

 selected from among thousands of normal skeletal parts (O. W. Geist, personal 

 communication). In a similar series of faunal remains from that island (see Bandi 

 and Blirgi 1972), I found also one pedal proximal phalanx and one tibia with 

 healed fractures. Murie (1936) speculated that the fractures were sustained as a 

 result of killer whale attacks, and this seems to me the most plausible 

 explanation. 



Schiller (1954:209) examined 17 of 52 walrus carcasses that washed ashore on 

 St. Lawrence Island in late October 1951 and concluded from reports of 

 intestinal prolapse, the presence of free blood in the abdominal cavity, and his 

 own observations of severe mutilation of the extremities, that they had been 

 killed by a "great and sudden external pressure," possibly "by concussion 

 resulting from an explosion." A series of blasts, heard by the St. Lawrence 

 Islanders in September of that year (and apparently connected with the 

 construction of new port facilities at Providence Bay, Chukotka), were 

 implicated as the possible cause of death. However, in retrospect, the probability 

 of damage by killer whales seems greater, for the following reasons: First, from 

 current knowledge of the distribution and migration of the Pacific walrus, it is 

 predictable that, although a group such as this, made up-mainly of adult females 

 and immature animals of both sexes, might have been as far south as the vicinity 

 of southern Chukotka in September-October, the probability of their having 

 been in Providence Bay at that time is extremely remote. Second, internal 

 hemorrhage, coupled with external mutilation of the extremities corresponds 

 most closely (in my experience) to the condition of animals mauled by killer 

 whales. Finally, in his examination of several skulls from these carcasses, Schiller 

 apparently did not notice any of the signs now known to be associated with death 

 of marine mammals from an external, explosive force (i.e., implosion of the 

 rigid-walled air spaces of the nasal passage and middle ear: Rausch 1973). Thus, 

 I feel that the evidence is strongly against death from an "explosive force," and 

 that predation by killer whales is a more plausible alternative. 



Harvests by Man 



For several millennia before the arrival of European man in the Bering- 

 Chukchi region, the indigenous Eskimo, Chukchi, and other native people 

 preyed on the Pacific walrus population to obtain food and other essential 

 raw materials (Collins 1937; Rudenko 1947; Arutiunov and Sergeev 1968). The 

 numbers of walruses that they killed each year probably did not approach the 

 number of deaths from other, "more natural" causes, for these were essentially 

 Stone Age hunters, who did not have the means or the incentive to take large 

 numbers of walruses. Indeed, they probably relied to a considerable degree on 



